Camillon, Imee Ruth B., Gargason, R-Dee A., Mallari, Astra Kristina B. (February 1999)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
Essential oils of garlic ( Allium sativum), onion (Onion cepa) and tamarind (Tamarindus indica), obtained through distillation of the crude extracts and macroextraction of the oils from the distillates, were screened for the presence of antibacterial activity on two test organisms: Gram- positive pathogen Staphylococus aureus and Gram- negative pathogen Escherichia coli, using the Bauer- Kirby Method. Tetracycline, a commercial drug, was used as positive control and distilled water was used as negative control.
One-Way Analysis of Variance proved that Diameter Zones of Inhibition formed by treatments did not vary significantly (p>0.05) on each test organism.
By getting the mean Diameter Zones of Inhibition of the treatments on the test organisms, it can be seen that in the two test organisims, Gram- positive pathogen Staphylococus aureus and Gram- negative pathogen Escherichia coli, all the essential oils exhibited antibacterial activities, and their mean Diameter Zones of Inhibition did not vary much from each other.